#!/bin/bash

function s1_generate_a_series_of_files(){
	for i in {1..100};
	do
		echo $i>/tmp/new_file$i;
	done
}

function s2_list_4_files_in_long_format_about_account_and_group(){
	ls -l /etc/{passwd,shadow,group,gshadow} | sort -d
}

function s3_find_items_related_to_given_username(){
	grep -h $1 /etc/{passwd,shadow} | sort -d	
}

function s4_find_items_related_to_given_group_name(){
	grep -h $1 /etc/{group,gshadow} | sort -d
}

function s5_create_groups_for_given_group_names(){
	groupadd rnd && groupadd itoperation 
}

function s6_create_users_and_set_their_group_as_required(){
	useradd -G rnd adam 
	useradd -G rnd bob 
	useradd -G rnd edward
	useradd -G itoperation calvin
	useradd -G itoperation david
}

function s7_change_users_shell(){
	usermod -s /usr/bin/sh adam && usermod -s /usr/bin/sh edward
}

function s8_set_password_change_policy(){
	chage -M 10 adam
	chage -M 10 bob
	chage -M 10 calvin
	chage -M 10 david
	chage -M 10 edward
	chage -m 60 -W 10 adam
	chage -m 60 -W 10 bob
	chage -m 60 -W 10 calvin
	chage -m 60 -W 10 david
	chage -m 60 -W 10 edward 
}

function s9_set_password_for_five_users(){
	usernames=(adam bob calvin david edward)
	for i in $(seq 0 4);
	do
		chpasswd <<< "$(($i + 1)):${usernames=[$i]}"
	done
}

function s10_lock_bobs_password(){
	usermod -L bob
}

function s11_include_adam_into_wheel_group(){
	usermod -aG wheel adam
}

function s12_change_files_permission(){
	for i in {1..33}; 
	do
		chmod -R  640 /tmp/new_file$[3*i];
	done
}
